Initial regression test for Wind Energy

Updates issue #13
Adding a find_element function to Form class

Updates issue #13
Fixing passing of parameters

Update issue #13
Method to locate GUI obj by element ID

Update issue #13
Add find_input() to gui.Application

To search for an element/input across all known windows, use the
convenience function in Application.
Update issue #13
Adding wrapper function for qt isEnabled()

Update issue #13
Testing aoi enables:land_polygon

Currently fails on the land_polygon inputs(which are dependent on the
AOI state).
Regards issue #13
Adding per-element emit_signals() methods

Update issue #14